Understanding this Circuit involving Relays

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The circuit in question involves relays controlled by a microcontroller, with inputs COM2 and COM3 feeding into the micro. The relays activate outputs RB4 to RB7, which can short connections 3 and 4, potentially allowing for a star-delta conversion. The user seeks clarification on the circuit's purpose and calculations related to phase voltage, specifically questioning the voltage at the microcontroller input. Initial calculations provided were incorrect, with the correct voltage determined to be approximately 0.885V. The discussion highlights a need for a clearer schematic to better understand the circuit's functionality.
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I need to understand the hardware circuit.
I need to understand the below circuit, the RB4, RB5, RB6, RB7 are controlled by the micro controller. The COM2 and COM3 are going as input to the micro. I know when the outputs RB4 to RB7 are ON, the relays will be ON and 3,4 get shorted. But i don't understand the purpose the circuit. Am i sorry that i don't have much details. Any comments can help me, I heard it can be used to change star to delta connection and vice versa. HardwareDiagram.jpg
 
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Just to add this is the circuit used for phase voltage, i need to understand. Can I assume that the calculations for Y phase voltage at the micro input is 560K and 560K in series and 10K in parallel
Hence for 100V for example
Voltage at micro = (100*10)/(560K + 560K + 10K) = 0.97V. Please advise, i am not going to design this circuit, this is only for understanding purpose.
 

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PhysicsTest said:
Voltage at micro = (100*10)/(560K + 560K + 10K) = 0.97V.
Check your arithmetic and the missing k multiplier ?
100V *( 10k / ( 10k + 560k + 560k ) ) = 0.885 V
 
PhysicsTest said:
But i don't understand the purpose the circuit. Am i sorry that i don't have much details.
The text is important. There is too much white space. Do you have a readable schematic ?
 
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